Rupturing head for fire extinguishers

ABSTRACT

A device for rupturing a pressurized cylinder containing a fire extinguishing product wherein when the temperature is high enough to melt the fusible link, it will cause a spring-loaded punch to forcibly propel the punch downwardly to rupture a rupturable disk in the cylinder to allow the contents to be ejected therefrom.

BACKGROUND OF THE INVENTION

The art is replete with devices employing a fusible link which melts at160° F. to release fire extinguishing gas from containers, such as U.S.Pat. Nos. to:

Mossberg 2,115,371;

Axtell 2,208,490;

Bakos 3,216,506;

Macartney 3,348,617;

Huthsing 3,613,793;

De Ronville 3,638,733;

Williams 3,884,306.

However, none of these patents disclose the novel features of theinstant invention.

SUMMARY OF THE INVENTION

The present invention provides a hollow housing, removably secured to acontainer having fire extinguishing material therein, said containerprovided with a neck having a rupturable disk therein, said housinghaving a cylindrically shaped upper half provided with apertures and anintegrally formed square in cross-section lower half, housing an axiallypositioned punch having a spring loaded seat portion and an offsettubular portion integrally formed on the lower end of the seat andhaving its free end sharpened, the area between the lower end of theupper half and the upper end of the tubular portion connected by a taperextending downwardly and inwardly. The punch is positioned and held ininoperative position by a pair of rotary pivoted arms held parallelly bya fusible link one on each side of said lower half of said housing, andmeans for securing the housing to a cylinder loaded with a fireextinguishing material under high pressure having a rupturable disk inits outlet end whereby when the link melts, the spring will cause thearms to be shifted laterally and the seat and tube to be forciblyprojected downwardly to rupture the disk and allow the contents of thecylinder to flow upwardly through the punch and outwardly to theatmosphere through the apertures in the housing to extinguish the fire.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of the present invention attached to afire extinguisher cylinder;

FIG. 2 is a top elevational view of FIG. 1 with parts broken away;

FIG. 3 is a vertical cross-sectional view taken on the line 3--3 of FIG.2;

FIG. 4 is an enlarged cross-sectional view of the details of one side ofthe rupturable disk in association with the lower end of the housing andpunch; and

FIG. 5 is a partial front elevational view of the housing and partiallyin cross-section.

DETAILED DESCRIPTION OF THE DRAWINGS

The housing 10 comprises a cylindrical hollow upper portion 12 and asquare in cross-section lower portion 14, which is provided with anaxial cylindrical bore. The portion 12 has a side wall 16 and a top wall18. Four apertures 20 are positioned equi-distantly in the wall 16adjacent the top wall, the purpose of which will hereinafter bedescribed.

The cylindrical punch 22 comprises a hollow seat 24 having a side wall26 and a tapered lower portion 28 to seat the lower end of the spring30. The upper end of the spring bears against the lower surface of thetop wall 18 of housing 10. The lower outer side wall 26 is tapereddownwardly and inwardly as at 29.

As clearly shown in FIG. 3, the wall 26 has a diameter smaller than theinner surface of the side wall 16 for easy shifting of the seat.

Integrally formed on the seat 24 and depending from the terminal end oftapers 28 and 29 is an offset cylindrical hollow elongated tube 34, thefree end of which is tapered to form a cutting edge 36. It is to benoted that the diameter of tube 34 is about one-half the diameter of theseat 24.

The lower portion 14 depends from and is integrally formed on the upperportion 12 and is also hollow and provided at its lower end withinterior threads 40 for attachment to the neck of the cylinder 42containing the fire extinguishing material.

The side walls 44, 46 are each provided with a slot 48 in which arms 50,52, respectively, loosely seat. The ends 54 of arms 50, 52 are looselypivoted to roll pins 56 seated in appropriate aligned bores in the lowerportion 14, as shown in FIGS. 2 and 3, with the lower ends of the pins56 pressfitted in the lower apertures 48' so as to anchor the pins 56and prevent accidental withdrawal thereof.

The free or opposite ends of arms 50, 52 are each provided with a hook60, 62 to receive the usual fusible link 63 by insertion in apertures66, 64, respectively, and thus retain the arms in parallellism, andpositioning the punch in the position shown in FIG. 3. As shown, thearms 50-52 are seated against the tapered wall 29.

A threaded hollow nut 68 is fitted to the neck 70 of the cylinder 42 toposition and hold a rupturable disk 72 in position on its seat 74 andprevent any emission of the contents from the container. It is to benoted that the outside diameter of the tube is smaller than the diameterof the inside wall of the lower portion 14 and interior of the hollowarea of the nut 68 for ready shifting of the punch axially therein.

The fusible link 63 melts when the temperature reaches 160° F. When thisoccurs, the punch will be urged downwardly under the action of thespring 30. The tapered wall 29 will thus force the arms 50, 52 outwardlylaterally about the pivot pins 56 and cutting edges 36 will penetrateand rupture the disk 72 to allow the ingredients to flow upwardlythrough the punch and to the surrounding outside area through apertures20 to quench any fire.

The fire extinguishing material in the container is preferablybromotrifluoromethane (common name Halon) under great pressure. Thischemical has the properties of quickly quenching fires, and particularlychemical fires.

The top wall 18 may also be provided with an aperture if desired forupward discharge of the material.

The device is resetable by employing a tubular tool to move the punchback against the spring force. The tool bears against the shoulder justbelow the taper 29. When the punch is forced back sufficiently, the arms50, 52 may be brought back to parallelism enough to place a new fusiblelink on their hooked ends. When the tool is removed, the tapered portion29 will force the arms outwardly to put the fusible link under tensionand thus place the head in condition for use again on a fresh cylinderof fire extinguishing material.

Although but one specific embodiment of this invention is herein shownand described, it will be understood that details of the constructionshown may be altered or omitted without departing from the spirit of theinvention as defined by the following claims.

I claim:
 1. A head for rupturing a disk in the cylindrical neck of acontainer for emission of fire extinguishing material, said neck havingmale threads around the exterior wall of the neck and a rupturable diskin said neck, in combination with a hollow housing having a top and sidewall, the upper portion being cylindrical, and having an integrallyformed substantially square in cross-section lower portion, .Iadd.anopening in said cylindrical upper portion, .Iaddend.said lower portionhaving a top and side and end walls, the lower end of said lower portionbeing internally threaded for securement to the neck of the container,said lower portion provided with a pair of opposed slots in said sidewalls and partially into said end walls, a pair of vertically disposedroll pins anchored to said side walls and each spanning one of saidslots, a hollow punch having a cylindrical spring loaded seat positionedinteriorally in the upper portion of said housing and a hollow tubularmember integrally formed on the lower end of said seat and offset fromsaid seat, the free end of said tubular member being sharpened to form acutting edge, a pair of arms each positioned in one of said slots, oneend of each of said arms pivotally secured to one of said roll pins, ahooked portion on the opposite end of each of said arms and a fusiblelink secured to said hooked portions to position said arms in paralleland support said seat in inoperative position.
 2. The device accordingto claim 1 wherein the lower end of said seat is tapered downwardly andinwardly and said tubular member depends from the lower portion of saidtaper and a spring in said seat portion.
 3. The device according toclaim 2 wherein each of said arms seat on said taper in inoperativecondition whereby when said fuse link melts under high temperature, thetaper will shift said arms outwardly about said roll pins under pressureof said spring and force said punch downwardly to rupture the disk insaid container neck.
 4. A fire extinguisher cylinder having a dischargeneck with a rupturable disk therein in combination with a discharge andperforator head removably secured thereto which comprises:a. a hollowhousing having a cylindrical upper portion having a side and top wallwith apertures in the side wall, and an integrally formed enlargedsquare in cross-section lower portion having top, side and end walls, aslot in each of said side walls extending the length of said side wallsand partially into said end walls and having communication with theinterior of said housing; b. a hollow cylindrical punch positionedaxially and loosely seated in said housing comprising an upper seatportion having a side wall, the lower interior and exterior ends of thewall of said upper seat portion being tapered downwardly and inwardly,and terminating in a depending hollow tubular portion integrally formedthereon and extending axially, the free end of said tubular.[.portions.]. .Iadd.portion .Iaddend.tapered .Iadd.downwardly and.Iaddend.inwardly .[.and outwardly.]. to form a cutting edge; c. aspring positioned in said upper portion of said punch seating betweenthe inner taper of said seat portion and the upper wall of said housing;d. a pair of arms, one seated in each of said slots, one end of each ofsaid arms pivotally secured to a vertically extending roll pin anchoredin the side walls of said lower portion of said housing and spanningsaid slots, the free ends of said arms each terminating in a hook; e. afusible link secured to and extending between each of the hooks in saidarms; f. and means to secure said housing to the neck of saidcontainer;said punch held in inoperative position by a portion of eachof said arms bearing against the exterior taper on the lower wall ofsaid seat portion; whereby when the temperature around the cylinder ishigher than the melting point of the link, the fusible link will melt,allowing the punch to push aside the retaining arms and proceeddownwardly at a high speed to perforate the rupturable disk in the neckof the fire extinguishing cylinder to allow the contents to flow undergreat pressure upwardly through the punch and outwardly through theapertures in the housing.